Conventionally, a high memory capacity and high input/output performance storage device is connected to many magnetic disk drives (hereinafter, abbreviated to “disks”). Such a storage device uses a configuration-information storing technology.
Configuration information, herein, is information about the configuration of a storage device. A storage device stores therein only the latest configuration information. An administrator acquires the latest configuration information from the storage device using a graphical user interface (GUI) of a maintenance personal computer (maintenance PC).
As described above, because the above storage device stores therein only the latest configuration information, if a failure occurs in the storage device, it is impossible to acquire at-the-time-of-failure configuration information. When a failure occurs in the storage device, the administrator first conducts recovery of the storage device. After the storage device recovers, the administrator acquires after-recovery configuration information and device logs and then confirms whether the storage device has actually recovered. After that, the administrator conducts a failure analysis using an estimation of the configuration information at the time of failure, this estimated configuration information being created using the acquired after-recovery configuration information and device logs. As described above, because the storage device acquires the latest configuration information after the storage device recovers, the storage device can acquire the after-recovery configuration information but it cannot acquire the at-the-time-of-failure configuration information.
Moreover, in the above configuration-information storing technology, the storage device stores therein only the latest configuration information; therefore, when device configuration is updated, the storage device has no previous configuration information. After the configuration information is updated using a GUI, even if there is a need for the previous configuration information, it is impossible to acquire the previous configuration information.
One approach to solving the above problems is to automatically store in a system disk, whenever the configuration information is updated due to a failure or in response to a GUI action, every piece of just-updated configuration information; however, because of a lack of system disk capacity, the storage device cannot adequately store therein the configuration information. A system disk has a given area and information that is needed to remain over a period of time regardless of whether the power is ON or OFF is stored in that area.
As described above, if just-updated configuration information is stored in a system disk whenever the configuration-information is updated, because of a lack of system disk capacity, the storage device cannot store therein the configuration information adequately. Especially in the event of chattering, where the status is switched to “error” repeatedly because of a component failure, and frequent component failures, the configuration information is updated frequently and every piece of updated configuration information will be stored. This leads to a lack of system disk capacity and overwriting of the configuration information; therefore, the storage device cannot store therein the configuration information adequately.
Patent Document: Japanese Laid-open Patent Publication No. 2008-262438